Starshot

Breakthrough Starshot is a research and engineering project by Breakthrough Initiatives to develop a proof-of-concept fleet of light sail spacecraft, named StarChip, capable of making the journey to the Alpha Centauri star system, 4.37 light-years away, at speeds between 15% and 20% of the speed of light, taking between 30 and 20 years to get there, respectively, and about 4 years to notify Earth of a successful arrival. The journey may include a flyby of Proxima Centauri b, an Earth-sized exoplanet that is in the habitable zone of its host star in the Alpha Centauri system. The conceptual principles to enable this interstellar travel project were described in "A Roadmap to Interstellar Flight", by Philip Lubin of UC Santa Barbara. Sending the lightweight spacecraft involves a square-kilometer with 10 kW lasers, operating as a phased array. This is needed for the spot size to fit the sail size at long range, so that the duration of the push is sufficiently long to reach these velocities. Getting sufficiently large effective aperture with one big laser would be impractical.

The project was announced on 12 April 2016 in an event held in New York City by physicist and venture capitalist Yuri Milner and cosmologist Stephen Hawking who is serving as board member of the initiatives. Other board members include Facebook CEO Mark Zuckerberg. The project has an initial funding of US$100 million to start research. Milner places the final mission cost at $5–10 billion, and estimates the first craft could launch around 2036.Pete Worden is the project's executive director.

Breakthrough Starshot aims to demonstrate proof of concept for ultra-fast light-driven nano-spacecraft, and lay the foundations for a first launch to Alpha Centauri within the next generation. Secondary goals are Solar System exploration and detection of Earth-crossing asteroids. The German physicist Claudius Gros has proposed that the technology of the Breakthrough Starshot initiative may be utilized in a second step to establish a biosphere of unicellular microbes on otherwise only transiently habitable exoplanets.

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